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VFD on a PM 1340 GT help for dummy
- Thread starter Latz55
- Start date
- Joined
- Dec 26, 2015
- Messages
- 2,148
Excellent decision.
Just a late follow-up. Mark built a system for me utilizing the Automation Direct DURApulse GS 20 series GS21-22 PO VFD I had purchased before I read his posts. This VFD was significantly different from the standard unit Mark has recommended, but he offered to figure out the programing rather than have me try to return it and purchase the other unit. I'm sure it was a lot of additional work on his part to get everything working. Mark sent me instructions and after cowboying up, my part was comparatively simple due to the extensive photos, detailed instructions and email questions answered. I've been using the lathe for a few weeks now and everything runs exactly as it should. Can't thank Mark enough for his time. I'm in a happy place - Thanks Mark!
I am getting ready to order a PM-1340GT. I do not have 3-phase power at my house. I am a little concerned with ordering a 3-phase machine and then immediately modifying it without even knowing it would run without modification. If I ordered a single phase machine, could I then later convert it to be powered by a VFD if I purchased a 3-phase motor or is the basic wiring of the single phase machine so different than the 3-phase that it would be a problem to go this route?
- Joined
- Jun 12, 2014
- Messages
- 5,071
If you do what I call the basic VFD install which uses the contactors to switch the low level inputs of the VFD, then no difference as you remove the high voltage wiring to the forward/reverse contactors. That being the case, there are so many advantages to going to 3 phase/VFD in particular on the 1340GT, there is noting to go wrong with a new 3 phase lathe like the 1340GT. Also the motor space is very small, so if replacing the single phase motor only certain TENV (small/short) 3 phase motors will fit. With 3 phase using a VFD, you get controlled acceleration, adjustable speed on the fly and most important controlled fast stopping. You also convert the lathe to a single pulley belt drive and do not need to switch the hi/low pulley settings. Technically going to 3 phase can result in a smoother surface finish when turning stock, this seems to vary, but has been reported by some people. You also do not need to deal with certain issues associated with single phase motors which is capacitor/start switch failure and failure of the motor to change direction if switched too quickly.
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1340gt surface finish problem
O.K. guys, and gals, I've tried every speed/feed combo, every carbide insert I have, every HSS tool I have, I've even put vibration isolation pads between the stand and the floor...nothing seems to work. Here's what I get... Please excuse my photography skills. You can not only SEE the...
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- Sep 1, 2020
- Messages
- 554
I agree with everything mksj posted about the benefits of going 3 phase with a VFD. To your original question of starting with single only to convert to 3 phase later. That seems like a lot of extra work. Especially if your only concern was to verify the machine ran correctly before your mod. I would check with PM but I am pretty sure they test every machine. Also there customer service is amazing so if that is your only concern, I recommend you talk to PM about it and ask how they test it and how they deal with warranty issues and when you make the VFD mod from day 1. They worked with me on this when I bought my 1440TL from them and warranty or support was never a concern for me. They were great to work with IMO.